August 23, 2012

Using Seawater To Fuel Nuclear Power

by editor

PNNL tests adsorbent to extract uranium from the ocean

When you take a dip in the ocean, nuclear fuel is probably the farthest thing from your mind. Uranium floats in Earth´s oceans in trace amounts of just 3 parts per billion, but it adds up. Combined, our oceans hold up to 4.5 billion tons of uranium — enough to potentially fuel the world´s nuclear power plantsfor 6,500 years.

Countries such as Japan have examined the ocean as a uranium source since the 1960s, but previous approaches have been too expensive to extract the quantities needed for nuclear fuel. Now researchers at the Department of Energy´s Pacific Northwest National Laboratory and Oak Ridge National Laboratory are tweaking one of those conceptswith the goal of making it more efficient and cost-competitive. The research is being done for the Department of Energy´s Office of Nuclear Energy.

Japan developed an adsorbent that attaches the uranium-loving chemical group amidoxime to a plastic polymer. ORNL examined the binding process between the plastic and chemical groups and used that knowledge to enhance the uranium-grabbing characteristic of the amidoxime groups on the adsorbent material´s surface.

PNNL tested the adsorbent´s performance at its Marine Sciences Laboratory in Sequim, Wash., DOE´s only marine research facility. Using filtered seawater from nearby Sequim Bay, PNNL established a laboratory testing process to measure the effectiveness of both Japan´s and ORNL´s adsorbent materials. Initial tests showed ORNL´s adsorbent can soak up more than two timesthe uranium than the material from Japan.